Cylinder oil



Patented Apr. 23, 1935 UNITED STATES PATENT OFFICE CYLINDER 01L Frederick H. MacLaren, Calumet City, and George F. Bowers, Chicago, 111., minors to Standard Company, Chicago, 111., a corporation of ana No Drawing. Application April 4, 1932,

. Serial No. 603,226

7 Claims. (oi. 87-9) This invention relates to lubricants for valves num stearate or equivalent soaps, asphaltic maor other mechanical parts that are exposed to terials, etc., and which thereby cause the formasteam, i. e., to cylinder oils" and the like. tion of a water-in-oil emulsion. The invention The object of the invention is to provide a is also applicable to lubricants which contain no lubricant which will withstand severe operating emulsifying agents. In either case the adhesive 5 conditions, which will maintain a continuous reand lubricating qualities of the oil are increased sistant lubricating film on and between the metal and the drop size accurately controlled. surfaces to be lubricated without gumming", and The following formulae will exemplify preferred which will provide superior lubrication with less embodiments of the invention:

10 I(aide-consumption than has heretofore been possi Example A P t 10 In a common type of lubricator, cylinder oils er cm are forced by a hydrostatic head through an orig z g z fi "".& fice (0.070 in. diameter) into a column of cony rogena e a s ree y 5 densed steam, and the emulsion thus. formed Example B lubrlcates the cylinder walls, valves, etc. It is Per cent highly desirable that the drops of oil be of small Miwcominent Steam r fined 9037 and uniform size so that constant and effective Aluminum stearate o3 lubrication may be accomplished With a mini- Hydrogenated ts 5% free tt 85 0 mum consumption of oil. Refined oils tend to have large drop sizes but refinement is necessary Eiwmple C to obtain other essential properties. Heretofore er cent special chemicals or agents, such as lead oleate, Mid-Continent steam refined 95.2 sperm oil, etc., have been used to lower and Aluminum stearate 0.8 I 5 regulate drop size. An object of our invention Hydrogenated fis Oil free fatty acid) 4.0 is to avoid theuse of such special chemicals or Example D agents, andat the same time to obtain a drop Per cent gigs of about .065 cc. which has been found de- Midcontment steam refined 93.2

able in practice. As I phaltic material 2.0 A further obJect 18 to provide a lubricant which 30 will increase the efficiency of the steam engines Hydrogenated fats Aluminum stearate 0.8

or compressors in which it is used. A further object is to provide a lubricant of this type at The oil in these examples may be described as less cost than has heretofore been possible. Other a heavy steam-refined Mid-Continent lubricating objects will be apparent from the following de- 011 having a flash point of about 530 F. and a 35 tailed description. viscosity at 210 F. of about 1'75 seconds Saybolt. We have discovered that when a heavy steam The flash point and viscosity are not critical refined oil is compounded with small amounts of and are determined by the particular lubrication hydrogenated fats, startling results are obtained. problem. Instead of using Mid-Continent steam Previous experiments showed that No. l lard oil refined lubricating oils we may use heavy Penn- 40 was superior as a compounding agent to prime sylvania steam refined oils or equivalent oils from lard oil, acidless tallow oil, degras, etc. We have other crudes. now discovered that hydr d f whi h The hydrogenated fats are prepared from mixpreferably contains a small amount of free fatty tures of fish oils, cotton seed oils, rape seed oils, acid, increases to a marked extent the desirable etc. Fish oils arepartici'ilafly d sir bl in 45 p'ropertiesof'these prior oils and in addition. it they contain largely unsaturated glycerides havaccomplishes a new result: it stabilizes the drop ing it carbon atoms (olein and its isomers, some size of the lubricant, and in the lubricator above of which are elaidin, iso-olein, and petroselinin) described it gives a drop size of 0.065 cc. We The titre of the hydrogenated acids is usually so dispense entirely with added stabilizers, and at controlled by suitably proportioning the amounts the same time we obtain-a greater uniformity of of cottonseed oil, rape seed oil, etc. which are drop. size than has been heretofore known in added to the fish oil, and for the present purlubricants of this type. pose 'we prefer to use an oil or fat with a titre Our invention may be applied to lubricants of of about 42 C. The particular process of hyto the ,invert emulsion" type which contain alumidrogenatlng these oils is 'well known (see D 8 8 372-430 of Hydrogenation of Organic Substances by Carleton Ellis, D. Van Nostrand Company, Inc., 250 Fourth Avenue, New York, Third Edition, 1930), and since it forms no part of the present invention it will not be described in detail. The hydrogenated oils are characterized by high saturation and uniformity, and they may be prepared with accurately regulated free fatty acid contents of from 0.5% to 20.0%. We do not limit ourselves to any particular hydrogenated oil, but we prefer to use hydrogenated fish oils.

The asphaltic material is preferably obtained from a cracked petroleum resin because asphalts of this type are .characterized by their fluidity at high temperatures. The asphalt in Example D has a melting point of about 135445 F. and a penetration of about 5-20 at 77 F.

The proportions stated in the above formulae are by way of example only and it may be generally said that the hydrogenated fat content may vary from about 2.0% to 15%, the aluminum stearate may vary from 0 to 2.0% and the asphaltic material from 0 to 5.0%. The effect of hydrogenated fats on heavy steam refined lubri eating oils does not depend on any particular proportion within the limits above stated, but depends rather on the compounding of the oil with said hydrogenated fat We have described the use of aluminum stearate as an emulsifier for obtaining water-in-oil emulsions, also called invert emulsions. It should be understood that any emulsifier with this property may be used instead of aluminum stearate, and particularly we may mention calcium stearate and iron stearate. Oleates may be used, but they may be objectionable from the standpoint of gum formation.

The drop size of an oil is determined by discharging the oil upwardly into hot water (about 200 F.) from an orifice about 0.070 in. in diameter under a head of about one or two inches of water, the drops issuing at the rate of about six per minute. Size is computed by dividing volume in cc. by the number of drops. Oils compounded with lard oil give drop size of 0.18 to 0.30 cc.much too large. By using sperm oil it has been possible to bring the drop size down to .08-.11 cc. but the size varies somewhat from time to time. We have discovered that by compounding these steam refined heav'ypils with hydrogenated fats we may obtain a uniform drop size of .065 cc. and that this drop size is the same, for instance, for a heavy paraffin oil as for a mixture of paraflin and Casper steam refined oils of equivalent viscosities.

In thelubrication of compressors, steam engines and similar apparatus it is common practice to supply the oil through a dropper or lubricator, and-it' is of extreme importance that the drop size be uniform and constant.

' The cylinder oils prepared in accordance with the above formulae have been subjected to severe laboratory tests and to tests on compressors and steam engines, particularly in lubricating Corlissvalves on steam engines. In engine tests the engine speed was maintained at about 4,000 to 5,000 revolutions per hour and .05 pounds of oil were used per thousand revolutions in all tests. As above described (see Examples A to D) the oils compounded gave perfect lubrication,-at no time was there any noise or undue vibration of .the valves, and at the end of three days, when the valves were inspected, there were perfect oil films with no signs of dry spots, no signs of wear, and no signs of the presence of gum on the valve ends. It was not necessary during the tests on these oils to add additional oil or to change the setting of the lubricator.

.. The drop size was uniformly about .065 cc. which insured dependable thorough and constant lubrication.

While .we have described in detail preferred embodiments of our invention, it should be understood that we do not limit ourselves to the details or proportions above described except as defined by the following claims which should be construed as broadly as the prior art will permit.

We claim:

1. A composition for lubricating steam cylinders and steam valves which composition consists essentially of a heavy hydrocarbon lubricating oil, about 1% to 10% of a hydrogenated fat, about 5% to 20% of free fatty acid, and a small amount of oil-soluble soap selected from theclass consisting of calcium stearate, iron stearate and aluminum stearate, the composition being normally liquid and characterized by a uniformly small drop size when introduced through the orifice of a lubricator into a steam cylinder.

2. The composition covered by claim 1 in which the hydrogenated fat is selected from the class consisting of fish oils, cotton seed oils, rape seed oils and mixtures thereof.

3. The composition of claim 1 which includes a small amount of asphaltic material.

4. A composition for lubricating steam cylinders and steam valves which consists essentially of a heavy steam-refined lubricating oil having a viscosity at 210 F. of the order of seconds Saybolt, and about 1% to 15% of a hydrogenated fat containing about .5% to 20% of free fatty acid, the composition being a liquid having a drop size of about .065 cc. when introduced through an orifice of .07 inch in diameter into water at about 200 F. at the rate of about 6 drops per minute.

5. The composition of claim 4 which includes a small amount of aluminum stearate.

6. The composition of claim 4 which includes a small amount of asphaltic material.

7. A composition for lubricating steam cylinders and steam valves which consists essentially of about 93.2% of heavy Mid-Continent steamrefined lubricating oil having a viscosity at 210 F. of about 175 seconds Saybolt, about 2% of asphaltic material, about 4% of hydrogenated fats, and about .8% of aluminum stearate.

FREDERICK H.'MACLAREN. GEORGE F. BOWERS. 

